The present invention relates to a semiconductor device having a large number of juxtaposed external drive terminals and, moreover, a liquid crystal display panel and a mobile information terminal equipped with such semiconductor device as a display driver, and also relates to a technique that is effectively applied to, for example, a mobile phone equipped with a small and high-definition liquid crystal display.
In an active matrix type liquid crystal display, the switching gates of a large number of thin-film transistors arranged in a matrix are turned on sequentially per scan line in accordance with horizontal synchronization timing, a driving voltage is supplied from source lines to the turned on thin-film transistors and thus applied to sub-pixels. This active matrix type liquid crystal display is widely used in a variety of mobile information terminals or the like typified by mobile phones and, as its display definition is enhanced to a higher definition, the number of external drive terminals increases. If the number of these external drive terminals increases, the external drive terminals of a liquid crystal display driver that drives the liquid crystal display have to be laid out at a narrower pitch. For example, when a liquid crystal display driver formed over a rectangular semiconductor substrate is placed along an edge of a liquid crystal display, as the number of source electrode lines which are led out from the edge of the liquid crystal display increases due to enhanced definition of the display, it becomes necessary to increase the number of external drive terminals to be formed in line with a long side of the liquid crystal display driver because of size limitation of the liquid crystal display driver.
Patent Document 1 describes laying out a plurality of arrays of both I/O pads as external terminals and I/O circuits coupled to the I/O pads in edge regions of a chip and enabling an increase in the number of I/O pads and I/O circuits of a semiconductor integrated circuit. It also mentions that the I/O pads are laid out in a staggered arrangement.
Patent Document 2 describes laying out input/output circuits which increase with increasing external terminals in a staggered arrangement, so that this arrangement can provide sufficient space for laying out the input/output circuits.